The present invention relates generally to a child-resistant closure device having a closure state indicating pattern. This allows the user to visually determine whether the cap is in a safe "child-proof" position or an unsafe position in which it may be removed from the threaded container by simple rotation.
More specifically, the subject invention is formed as a three-element child-resistant container closure, with the three elements coaxial and nested one within the other. The outermost element is arranged for rotation relative to the centrally-located or middle element. The outermost element is provided with a window which is registrable with indicia provided on the central element. The outermost and central elements cooperate in a torquing manner so that, as the closure is rotated to close the container, an indication of full sealing is viewable through the window of the outermost cap only when such sealing is complete. Similarly, during rotative unsealing or opening of the container, the outermost member first moves relative to the remainder of the closure so that the window moves out of register with the full sealing indicium and into register with an unclosed indicium to give an indication viewable through the window just as soon as rotative opening of the container has begun that the closure no longer seals. Thus, the closure provides the user with a readily apparent indication as to whether or not the container closure is in its fully closed or container-sealing condition.
Child-resistant closure devices for containers having a threaded neck are known and are described. However, prior art attempts have suffered from various drawbacks as discussed below.
For example, U.S. Pat. No. 3,216,600 to Dreps discloses a container and closure cap combination having a screw thread formation which insures proper registry of the surface decoration applied to the container and the closure cap. Thus, a directional closure cap and container combination is disclosed wherein both accurate registration of decorative matter on the closure cap and container and reliable sealing are obtained. This reference, however, does not teach the use of a closure state indicating pattern viewable through a window of the outer cap.
U.S. Pat. No. 4,271,971 to Morris discloses a three component safety cap for use on threaded containers which is rotationally operated so that the cap is either in a safe or "child proof" mode or an unsafe mode in that it may be removed from the threaded container by simple rotation. Optionally, the safety cap may include a visual indicator of its safe or unsafe condition. However, there is no indication in the reference of an outer cap having means for frictional engagement in order to provide an increasing interference fit between the middle and outer caps when the outer cap is rotated in a closed direction, as taught herein.
U.S. Pat. No. 4,500,005 to Forrester discloses a tamper-evident cap assembly for a container having an externally screw-threaded top which ratchets from position to position. The outer cap has a window with the inner cap having an insignia which is not visible in the window when the outer cap is in its initial relatively clockwise position relative to the inner cap. This visual indicator operates as to whether the package has ever been opened. This reference, however, does not teach a child-resistant cap nor a three element cap in which the outer cap has means for frictional engagement with a radially differing groove portion of a middle cap which provides for an increasing interference fit between the middle and outer caps so that an indicating pattern of full sealing is viewable through a window on the outer cap, as taught herein.
U.S. Pat. No. 4,826,000 to Danker et al. discloses a container for storing contact lenses and conditioning them with a liquid that releases gas, with the container having a visual indicator in order to determine a desired container tightness. There is no indication in the reference of an indicating pattern of full sealing that is torqued in and out of position.
None of the prior art, however, teaches or suggests a child-resistant closure having indicating means formed of an inner cap, a middle cap and an outer cap and a means for frictional engagement with a radially differing groove portion of the middle cap in order to provide an increasing interference fit between the middle and the outer caps as the outer cap is rotated in one direction. Moreover, no other prior art reference discloses an outer cap which first frictionally engages a middle cap in a torquing manner causing the middle cap to remain stationary relative to the outer cap, with complimentary knurlings on the middle and inner caps also causing the inner cap to remain stationary relative to the outer cap so that as force is applied to rotate the outer cap to close the container, the threaded portion of the inner cap seals the threaded portion of the container.
It is, therefore, an object of the invention to provide a child-resistant closure which is rotatable for indicating whether the closure is in its fully sealing condition.
Another object of the invention is to provide a simple child-resistant closure with means for indicating whether the cap is in a fully closed condition.
A further object of the invention is to provide a child-resistant closure with indicating means which can be readily installed on a bottle during a manufacturing process.
Still other objects and advantages of the invention will in part be obvious and will in part be apparent from the specification.